def sol a, h
    if a.size < 3
        return 0
    end
    r = a.pop
    l = a.shift 
    h[l] -= 1
    h[r] -= 1
    tmp = 0
    idx = 10000
    a.size.times{|i|
        if [l,a[i],r].uniq.size == 3 && tmp < h[a[i]]
            tmp = h[a[i]]
            idx = i
        end
        }
    if idx == 10000
        return 0
    end
    a.delete_at(idx)
    h[idx] -= 1
    return sol(a, h) + 1
end

gets.to_i.times{
    n = gets.to_i
    a = gets.split.map(&:to_i).sort
    h = Hash.new(0)
    a.each{|x|
        h[x] += 1
        }
    p sol(a, h)
    }